Production of iodophors of chlorinated alkoxylated wool grease

ABSTRACT

A PROCESS FOR THE PRODUCTION OF WATER-SOLUBLE WOOL GREASE IN WHICH ALKOXYLATED WATER-SOLUBLE WOOL GREASE IS CAUSED TO COMBINE WITH CHLORINE TO REDUCE THE IODINE VALUE BY 50% TO 95%.

United States Patent US. Cl. 260-408 8 Claims ABSTRACT OF THE DISCLOSURE A process for the production of water-soluble Wool grease in which alkoxylated water-soluble wool grease is caused to combine with chlorine to reduce the iodine value by 50% to 95%.

This invention relates to improved iodophors containing chlorinated water-soluble wool grease derivatives.

It is well known to prepare water-soluble derivatives of wool grease or related substances by reacting these substances with ethylene or alkylene oxide so as to provide polyalkylene oxide chains of a length sufiicient to impart the desired solubility, the mean chain length required varying from substance to substance. By wool grease is to be understood here the crude grease recovered by centrifuging or acidifying wool scouring liquor, or that which is extracted from wool by organic solvents. By related substances is implied refined wool fat otherwise known as anhydrous lanolin or chemical and physical derivatives thereof which retain an active hydrogen atom capable of initiating the desired reaction, for example lanolin alcohols, lanolin fatty acids, lanolin oil, deoiled lanolin, acetylated lanolin, lanolin fatty acid esters and hydrogenated lanolin. Other examples of related substances are wool grease fatty acids defined as the by-products of refining wool grease to lanolin, and esters thereof.

The uses of alkylene oxide compounds of wool grease and wool grease derivatives are many, for example as water-soluble surfactants, detergents, solubilisers, emollients, hair conditioners, emulsifiers and as a base for iodophor preparations.

The use of ethoxylated lanolin in iodophors is made known in British Pat. No. 1,144,637 but in such products, as in iodophors in general based on other surfactants, all the iodine which is added during manufacture does not remain available in the free, germicidally-active state, as a proportion of the total iodine invariably combines chemically and irreversibly with the surface active agent in a form which is germicidally inactive. The loss of active iodine by combination in this way is clearly undesirable and adds to the cost of the iodophor.

The invention comprises a process for the manufacture of a product in which' alkoxylated water-soluble wool grease or related substance as herein defined is caused to combine with chlorine so as to reduce the iodine value by 50% to 95%.

The mechanism involved in the irreversible combination of the surfactant with iodine is not known with certainty but it has been suggested as comprising the reaction of iodine with free hydroxyl groups in the surfactant molecules and in accordance with the present invention another possible mechanism is postulated, namely a reaction at double bonds or points of unsaturation in the surfactant molecules. By way of illustration it is well known that wool grease and its derivatives are unsaturated and that they can combine chemically with halogens as evidenced by the fact that they have a measurable iodine value which is obtained in the art as the number of parts of iodine which will react and combine with 100 parts by weight of a given substance. Iodine value is an official requirement of the British Pharmacopoeia 1968 in respect of anhydrous lanolin, the limits of 18 to 32 being stipulated.

Whilst it is not the intention of the present invention to claim with any certainty that the loss of active iodine in iodophors is by reaction at points of unsaturation, it has nevertheless been discovered that if the unsaturation of alkoxylated wool grease or wool grease derivatives is reduced by a clorination process prior to the incorporation thereof in iodophors, the reduction in unsaturation is demonstratable by a lowering of the iodine value of the alkoxylated wool grease, and the proportion of the total iodine which is irreversibly lost in the iodophor is significantly reduced.

The clorination of the alkoxylated wool grease or wool grease derivatives may be achieved by methods known in the art relating to organic chlorinations, for example by direct reaction with gaseous chlorine, with thionyl chloride or chlorides of phosphorus or by reaction with organic chlorine donors such as dichlorodimethylhydantoin or trichloroisocyanuric acid. With organic chloride d0- nors such as those exemplified it has been found advantageous to carry out the chlorination in the presence of water which appears to facilitate and intensify the reaction. The chlorine combined in the finished product should be between 1% and 4% by weight.

The following examples serve to illustrate ways in which the invention may be carried out:

EXAMPLE 1 1,000 g. of ethoxylated wool grease mols. ethylene oxide) were mixed with 333 g. of water and warmed to 50 C., whereupon g. of powdered Hydan (a commercial brand of dichlorodimethylhydantoin) were added little by little with stirring over a period of approximately 30 minutes keeping the temperature of the reaction mixture at 50-55 C. When all had been added the stirring was contained for a further 15 minutes. Tests showed the product to contain 1.8% by weight of chlorine and the iodine value of the ethoxylated wool grease to have been reduced from 8.1 to 0.5, indicating 93.8% efliciency of chlorination.

From the reaction product an iodophor was prepared according to the formula:

Percent w./w.

The iodophor had an available iodine content of 1.60% by weight, whereas one made to the same formula but using unchlorinated ethoxylated wool grease showed only 1.05%.

EXAMPLE 2 1,000 g. of ethoxylated anhydrous lanolin (60 mols. ethylene oxide) were mixed with 500 g. of water and warmed to 50 C. whereupon 100 g. of powdered Fichlor 91 (a commercial brand of trichlorisocyanuric acid) were added little by little over a period of 30 minutes. When all had been added stirring was continued for a further 15 minutes. Tests showed the iodine value of the ethoxylated lanolin to have been reduced from 9.0 to 1.0, indicating 88.9% efficiency of chlorination. The chlorine content of the product was 2.1%.

From the reaction product an iodophor as specified in Example 1 was prepared, which gave an available iodine content of 1.61% compared to 1.11% when the unchlorinated ethoxylated lanolin was used.

EXAMPLE 3 1,000 g. of ethoxylated lanolin oil (100 mols. ethylene oxide) were warmed to 50 C. with stirring whilst gase- EXAMPLE 4 A series of chlorinations were carried out as in Example 1 in which the ratio of Hydan to ethoxylated Wool grease was varied. From each chlorinated product the same iodophor was prepared, with the following results:

Ratio, hydanzethoxylated wool grease.-.- 1:30 1:15 1:10 lfi' Iodine value or produce 3. 1 0. 9 0. 5 0. 4 Perceht etficiency of chlorination- 61. 7 88. 9 93. 8 95. 1 Percent available iodine in iodophor 1.05 1. 20 1. 46 1.60 1. 62

Example 4 illustrates how the available iodine content in the iodophor is a function of the extent of chlorination of the ethoxylated wool grease, but that there appears to be little further advantage to be gained in chlorinating more than about 94% of the substance. Dichlorodirnethylhydantoin is referred to in the table as Hydan.

The temperature during the chlorination process is not very important and may lie between 25 and 95 C. although the range 5060 C. is preferred. When using organic chlorine donors such as Hydan and Fichlor the water present may be between and 100% of the weight of the alkoxylated wool grease or derivative thereof, the preferred range being 25 to 50%.

As an alternative to iodophors based entirely on chlorinated water-soluble wool grease derivatives as herein described other surfactants as known in the art may be used in conjunction therewith, as now illustrated in Example 5:

EXAMPLE 5 Ethoxylated wool grease was chlorinated in the manner described in Example 1 and the resultant product was used to prepare an iodophor according to the formula:

Percent w./w.

Chlorinated ethoxylated wool grease 16.56 Empilan NP 9 11.51 Iodine 3.00 Industrial methylated spirits (74 op.) 5.00 Water 63.93

What I claim is:

1. A method for producing an improved iodophor composition in which iodine is complexed wholly or partially by a chlorinated alkoxylated wool grease derivative of which the iodine value has been reduced by chlorination by 50% to 2. A method for producing an iodophor composition as in claim 1 in which the chlorinated alkoxylated wool grease derivative contains between 1% and 4% of chlorine by Weight.

3. A method for producing an iodophor composition as in claim 1 in which the alkoxylated wool grease derivative is chlorinated by chloro-derivatives of dimethylhydantoin or isocyanuric acid in the presence of 10% to of water relative to the alkoxylated Wool grease derivative.

4. A method for producing an iodophor composition as in claim 1 in which the alkoxylated wool grease derivative is chlorinated by chloro-derivatives of dimethylhydantoin or isocyanuric acid in the presence of 25% to 50% of water relative to the alkoxylated wool grease derivative.

5. A method for producing an iodophor composition as in claim 1 in which the alkoxylated wool grease derivative is chlorinated by elemental chlorine.

6. A method for producing an iodophor composition as in claim 1 in which the alkoxylated wool grease derivative is chlorinated at a temperature between 25 C. and 95 C.

7. A method for producing an iodophor composition as in claim 1 in which the alkoxylated wool grease derivative is chlorinated at a temperature between 50 C. and 60 C.

8. A method for producing an iodophor composition as in claim 1 in which the alkoxylated wool grease derivative comprises ethoxylated wool grease.

References Cited UNITED STATES PATENTS 2,290,583 7/1942 Dreger et a1. 260408 2,449,547 9/1948 Byrkit 260408 2,986,555 5/1961 Paterson 260-82.3 2,279,734 4/ 1942 Dreger et al 260-417 2,840,510 6/1958 Katz et a1 424-l50 FOREIGN PATENTS 1,144,637 3/1969 Great Britain.

LEWIS GOTIS, Primary Examiner D. G. RIVERS, Assistant Examiner US. Cl. X.-R. 

